"The recent flood waters have exacerbated the damage and if it isn’t sorted out immediately it will continue to disintegrate and there will be deaths as cars/people/buses plunge into the river beneath.”

Calderdale Council has played down fears and, in a tweet, a spokesman said: “We’ve inspected Huddersfield Road bridge in Brighouse which is safe to use. Another inspection will take place tomorrow (Thursday).”

The bridge is used by buses and heavy vehicles and while the main crack is thought to have been there some time it is feared water damage could have made it worse.

Meanwhile, concerns are mounting over Elland Bridge with the authorities fearing the damage could be worse than first thought.

The bridge is owned by the Canal and River Trust and the organisation, a charity, has warned it only has limited resources.

Trust chiefs will be looking to work with the council and the Government and a spokesman said: “We will be looking at all the options available to us this week and next.”

In a statement a Calderdale Council spokesman said: “We are aware of major highways issues at sites such as Elland Bridge and the A646 in Upper Valley, and we continue to inspect all built structures along the Calder Valley to check that they are safe and undamaged.

“We urge people to only make essential journeys around the affected areas to allow the clean up to continue and to keep roads clear for emergency services and recovery vehicles. The council is focusing their efforts on repairing and managing this.”